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joel-garry_at_home.com (Joel Garry) wrote in
news:91884734.0408031400.1f610f57_at_posting.google.com:
> Chuck <chuckh_nospam_at_softhome.net> wrote in message
> news:<Xns953A5DA207E9Achuckhnospamsofthome_at_130.133.1.4>...
>> Mladen Gogala <gogala_at_sbcglobal.net> wrote in >> news:pan.2004.08.03.10.38.29.471246_at_sbcglobal.net: >> >> > On Mon, 02 Aug 2004 18:32:56 +0000, Chuck wrote: >> > >> >> After moving an oracle datafile, it sometimes takes hours or even >> >> days for the space to become free in the filesystem that the >> >> datafile was moved from. Why is this? Is there a way force Oracle >> >> to release this space without restarting the instance? >> >> >> >> Platform AIX 4.3, Oracle 8.1.7.4 >> > >> > Unmount the file system and re-mount it again. >> > >> >> This is a 24x7x364 production database. There are other datafiles on >> that filesystem. Unmounting and remounting are not an option. Neither >> is bouncing the instance which also frees up the space immediately.
Prior to moving the file about 20 oracle processes had it open. 19 of them were Oracle background processes (dbw0, ckpt, etc.) Immediately after moving it only 1 did and that was a user's shadow process. The original filesystem's free space remained the same before and after moving it. I decided to try forcing a checkpoint to see if that would release the space and it did. Was it coincidence? Maybe. If I can consistently release the space with a checkpoint though I will be inclinded to think it's an Oracle problem.
Could it be a unix problem? Maybe. But I've seen it on every Oracle platform I've ever used, including Windows.
One other thing I want to try is to copy the file instead of moving it, then cat /dev/null over top of the original before rm'ing it. Not sure if this will prove it's a unix problem or not but if it consistently releases the space who cares. That's the real objective.
-- Chuck Remove "_nospam" to reply by emailReceived on Wed Aug 04 2004 - 15:34:39 CDT